Assessment of individual and population-based sampling for detection of Influenza A virus RNA in breeding swine herds

Abstract

This study compared the probability of influenza A virus (IAV) ribonucleic acid (RNA) detection between selected individual and population-based samples in breeding herds. A 3500-sow breeding herd was sampled for matched sets (n = 57) of family oral fluids (FOF), udder wipes, sow nasal wipes, individual piglet nasal wipes, and drinker wipes and tested by reverse transcription real-time polymerase chain reaction (RT-rtPCR) for IAV RNA detection. Overall, 57.9% (33/57) of FOF samples, 49.1% (28/57) of udder wipes, 28.1% (16/57) of sow nasal wipes, 15.8% (9/57) of drinker wipes and 66.6% (38/57) of the individual piglet nasal wipes tested positive for IAV RNA. FOF had a kappa value of 0.81, a near-perfect agreement compared to individual piglet nasal wipes. Udder wipes revealed a kappa value of 0.65, a substantial agreement with individual piglet nasal wipes. The other sample types had a fair agreement with individual piglet nasal wipes (kappa values <0.28). These results validate FOF as an efficient alternative population-based sample type for IAV surveillance in the breeding herd. The proportion of positive piglets within litter by room A had 91% positivity (20/22), room B had 70% (17/24), and room C had 9% (1/11) positivity. The findings also highlight the importance of testing different farrowing rooms in the same breeding herd to strengthen IAV surveillance.This article is published as Moraes, D. C. A., P. C. Gauger, O. H. Osemeke, I. F. Machado, G. Cezar, R. Paiva, M. Mil-Homens et al. "Assessment of individual and population-based sampling for detection of Influenza A virus RNA in breeding swine herds." Science Talks (2024): 100362. doi: https://doi.org/10.1016/j.sctalk.2024.100362. © 2024 The Authors. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)